660 research outputs found
Macular edema after surgical treatment of rhegmatogenous retinal detachment – the possibilities of its prediction
The aim: to develop a mathematical model for predicting macular edema based on the informativeness of clinical and instrumental predictors of its occurrence.Materials and methods. To determine the risk factors for macular edema 64 patients (64 eyes) with macula-off rhegmatogenous retinal detachment complicated by proliferative vitreoretinopathy (grade Cp 1–2) were selected. A retrospective analysis of the surgical treatment results was carried out. The age of the patients ranged from 30 to 81 years (28 women and 36 men).Results. Using regression analysis, two signifi cant factors were identifi ed: the sum of 8 meridians of the visual fi eld before surgery (p = 0.015) and the number of detached quadrants (p = 0.021). Based on the identifi ed factors, a model was obtained for predicting the occurrence of macular edema in the postoperative period for the patients with rhegmatogenous retinal detachment. Conclusion. Based on the analysis of clinical and instrumental indicators in patients with rhegmatogenous retinal detachment, a mathematical model has been developed that allows predicting the occurrence of macular edema in the postoperative period.The application of the proposed prediction model makes it possible to determine the tactics of treatment (peeling of internal limiting membrane) and predict the appearance of macular edema at the preoperative stage
ВПЛИВ ЗАНЯТЬ СПОРТОМ НА ФУНКЦІОНАЛЬНІ МОЖЛИВОСТІ СЕРЦЕВО-СУДИННОЇ СИСТЕМИ ДІВЧАТ 17-21 РОКІВ ПОДІЛЬСЬКОГО РЕГІОНУ
In this article considers the effectiveness of the impact of sports on the functionality of the cardiovascular system of girls 17-21 years old living within the Podolsk region. The function of the cardiovascular system of girls was evaluated by the ability to recover after termination of work (by the parameters of heart rate). Classes cycling and playing sports (performance of muscle work of which is connected with the mixed mode of power supply) and martial arts (performance of muscular work is associated with anaerobic (lactate) mode of power supply) contribute to improvement the functional possibilities of the cardiovascular system. This is manifested by the acceleration of recovery of heart rate after metered physical loads of 1 watts and 2 watts per 1 kg of body weight. The smallest percentage of person with a slow recovery of heart rate were detected among athletes, volleyball players and representatives of complex coordination sports. These individuals are involved in the performing of physical exercise with anaerobic (alactate) processes of metabolism.In this article considers the effectiveness of the impact of sports on the functionality of the cardiovascular system of girls 17-21 years old living within the Podolsk region. The function of the cardiovascular system of girls was evaluated by the ability to recover after termination of work (by the parameters of heart rate). Classes cycling and playing sports (performance of muscle work of which is connected with the mixed mode of power supply) and martial arts (performance of muscular work is associated with anaerobic (lactate) mode of power supply) contribute to improvement the functional possibilities of the cardiovascular system. This is manifested by the acceleration of recovery of heart rate after metered physical loads of 1 watts and 2 watts per 1 kg of body weight. The smallest percentage of person with a slow recovery of heart rate were detected among athletes, volleyball players and representatives of complex coordination sports. These individuals are involved in the performing of physical exercise with anaerobic (alactate) processes of metabolism
Features of pathological changes in the retina and vitreoretinal interface in the macular zone in patients with diabetic macular edema
Background. Diabetic macular edema (DME) is one of the main causes of decreased central vision. Determining the reasons for the refractoriness of DME to treatment is an urgent problem.Aims. Based on the analysis of optical coherence tomography, to study the features of pathological changes in the retina and vitreoretinal interface (VRI) in the macular zone in patients with DME.Materials and methods. We studied 587 patients (587 eyes) with diffuse DME in the setting of nonproliferative diabetic retinopathy. In addition to the standard ophthalmological examination, everyone underwent optical coherence tomography of the macular zone with an assessment of structural changes in the retina, morphometric parameters, and the state of the VRI.Results. In 351 patients (59.80 %) with DME, pathological variants of the VRI were revealed, in which the best corrected visual acuity was significantly lower, and the morphometric parameters (retinal thickness and macular volume) were signifi cantly higher. Analysis of morphostructural changes in the macular zone revealed that in pathological VRI, neuroepithelial detachment and high edema are more common, and cystic edema is larger in area compared to the group with a normal VRI. With detachment of neuroepithelium against the background of a pathological VRI, the worst morphometric data are determined, with solid exudates in the macula, the worst indices of visual loss are determined.Conclusions. The pathological VRI in patients with diabetic macular edema occurs in more than half of the cases and is characterized by a high incidence of neuroepithelial detachment, high edema, higher morphometric parameters with worse visual acuity. At the same time, the presence of neuroepithelial detachment corresponds to the worst morphometric indicators of the macular zone, and the presence of solid exudates corresponds to a lower maximum corrected visual acuity. Further research is needed to assess the effect of the listed morphostructural and morphometric changes in combination with various pathological variants of VRI on the effectiveness of DME treatment
Evidence for Narrow N*(1685) Resonance in Quasifree Compton Scattering on the Neutron
The first study of quasi-free Compton scattering on the neutron in the energy
range of GeV is presented. The data reveals a narrow
peak at GeV. This result, being considered in conjunction with
the recent evidence for a narrow structure at GeV in the
photoproduction on the neutron, suggests the existence of a new nucleon
resonance with unusual properties: the mass GeV, the narrow width
MeV, and the much stronger photoexcitation on the neutron than
on the proton.Comment: Replaced with the version published in Phys. Rev.
Possible use of corneal lenticule in surgery of corneal diseases (literature review)
In this review, we analyzed the domestic and foreign literature on the use of corneal lenticula obtained by keratorefractive surgery using the SMILE technology (SMall Incision Lenticula Extraction). Research is being actively carried out on the use of a lenticular tissue for refractive purposes: for the correction of hyperopia (LIKE – Lenticular Intrastromal Keratoplasty), for the correction of presbyopia (PEARL – PrEsbyopic Allogenic Refractive Lenticule). A significant amount of works are devoted to the use of lenticular tissue for the treatment of keratectasias of various origins. For example, a number of authors for the treatment of keratoconus suggest implantation of a lenticule into the recipient’s corneal pocket formed by a femtolaser (SLAK – Stromal lenticule addition keratoplasty). Clinical cases of combined treatment are described: implantation of a lenticule and corneal intrastromal segments for the treatment of corneal pellucid degeneration. A large number of works are devoted to the use of lenticules for tectonic coverage of ulcerative defects, marginal thinning in Mooren’s ulcer. Several clinical cases of the use of a corneal lenticule to cover a deep corneal defect in recurrent pterygium are described. This review also included articles on the storage and decellularization of corneal lenticules. The analyzed articles show a wide area of application of the corneal lenticule; however, more research is required in each of the areas of application, and it is also necessary to solve the problem of procurement and storage of lenticular tissue
Mathematical modelling of the liquid atomization process by cocurrent gas flow
This paper focuses on the physical-mathematical model of liquid atomization in the spray pattern of an ejection nozzle. A flow field of a gas phase behind the nozzle section is computed using the Ansys Fluent package. Dynamics of molten metal droplets in the gas phase within a trajectory approach is calculated. Using the presented model, numerical calculation results are given
Synthesis of nanostructure yttrium-aluminum garnet powders activated with cerium, europium, gadolinium and their luminescent characteristics
Surface alignment and anchoring transitions in nematic lyotropic chromonic liquid crystal
The surface alignment of lyotropic chromonic liquid crystals (LCLCs) can be
not only planar (tangential) but also homeotropic, with self-assembled
aggregates perpendicular to the substrate, as demonstrated by mapping optical
retardation and by three-dimensional imaging of the director field. With time,
the homeotropic nematic undergoes a transition into a tangential state. The
anchoring transition is discontinuous and can be described by a double-well
anchoring potential with two minima corresponding to tangential and homeotropic
orientation.Comment: Accepted for publication in Phys. Rev. Lett. (Accepted Wednesday Jun
02, 2010
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